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<tr><td colspan="5" class="shortcuts"><nobr><a href="#id2751815" class="shortcut">Top</a>
                  &#160;|&#160;
                  <a href="#id2843520" class="shortcut">Description</a>
                  &#160;|&#160;
                  <a href="#id2843434" class="shortcut">Object Hierarchy</a>
                  &#160;|&#160;
                  <a href="#id2843458" class="shortcut">Prerequisites</a>
                  &#160;|&#160;
                  <a href="#id2843480" class="shortcut">Known Implementations</a></nobr></td></tr>
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<div class="refentry" lang="en">
<a name="GSeekable"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2>
<a name="id2751815"></a><span class="refentrytitle">GSeekable</span>
</h2>
<p>GSeekable &#8212; Stream seeking interface</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<pre class="synopsis">

#include &lt;gio/gio.h&gt;


                    <a class="link" href="GSeekable.html#GSeekable-struct">GSeekable</a>;
                    <a class="link" href="GSeekable.html#GSeekableIface">GSeekableIface</a>;
<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
>goffset</a>             <a class="link" href="GSeekable.html#g-seekable-tell">g_seekable_tell</a>                     (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable);
<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            <a class="link" href="GSeekable.html#g-seekable-can-seek">g_seekable_can_seek</a>                 (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable);
<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            <a class="link" href="GSeekable.html#g-seekable-seek">g_seekable_seek</a>                     (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
>goffset</a> offset,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-IO-Channels.html#GSeekType"
>GSeekType</a> type,
                                                         <a class="link" href="GCancellable.html" title="GCancellable">GCancellable</a> *cancellable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Error-Reporting.html#GError"
>GError</a> **error);
<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            <a class="link" href="GSeekable.html#g-seekable-can-truncate">g_seekable_can_truncate</a>             (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable);
<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            <a class="link" href="GSeekable.html#g-seekable-truncate">g_seekable_truncate</a>                 (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
>goffset</a> offset,
                                                         <a class="link" href="GCancellable.html" title="GCancellable">GCancellable</a> *cancellable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Error-Reporting.html#GError"
>GError</a> **error);


</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2843434"></a><h2>Object Hierarchy</h2>
<pre class="synopsis">

  GInterface
   +----GSeekable
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2843458"></a><h2>Prerequisites</h2>
<p>
GSeekable requires
 <a
href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject"
>GObject</a>.</p>
</div>
<div class="refsect1" lang="en">
<a name="id2843480"></a><h2>Known Implementations</h2>
<p>
GSeekable is implemented by
 <a class="link" href="GFileOutputStream.html" title="GFileOutputStream">GFileOutputStream</a>,  <a class="link" href="GMemoryInputStream.html" title="GMemoryInputStream">GMemoryInputStream</a>,  <a class="link" href="GMemoryOutputStream.html" title="GMemoryOutputStream">GMemoryOutputStream</a> and  <a class="link" href="GFileInputStream.html" title="GFileInputStream">GFileInputStream</a>.</p>
</div>
<div class="refsect1" lang="en">
<a name="id2843520"></a><h2>Description</h2>
<p>
<a class="link" href="GSeekable.html" title="GSeekable"><span class="type">GSeekable</span></a> is implemented by streams (implementations of 
<a class="link" href="GInputStream.html" title="GInputStream"><span class="type">GInputStream</span></a> or <a class="link" href="GOutputStream.html" title="GOutputStream"><span class="type">GOutputStream</span></a>) that support seeking.</p>
<p>

</p>
</div>
<div class="refsect1" lang="en">
<a name="id2843562"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id2843572"></a><h3>
<a name="GSeekable-struct"></a>GSeekable</h3>
<a class="indexterm" name="id2843585"></a><pre class="programlisting">typedef struct _GSeekable GSeekable;</pre>
<p>
Seek object for streaming operations.</p>
<p>

</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2843603"></a><h3>
<a name="GSeekableIface"></a>GSeekableIface</h3>
<a class="indexterm" name="id2843616"></a><pre class="programlisting">typedef struct {
  GTypeInterface g_iface;

  /* Virtual Table */
  
  goffset     (* tell)	         (GSeekable    *seekable);
  
  gboolean    (* can_seek)       (GSeekable    *seekable);
  gboolean    (* seek)	         (GSeekable    *seekable,
				  goffset       offset,
				  GSeekType     type,
				  GCancellable *cancellable,
				  GError      **error);
  
  gboolean    (* can_truncate)   (GSeekable    *seekable);
  gboolean    (* truncate_fn)    (GSeekable    *seekable,
				  goffset       offset,
				  GCancellable *cancellable,
				  GError       **error);

  /* TODO: Async seek/truncate */
} GSeekableIface;
</pre>
<p>
Provides an interface for implementing seekable functionality on I/O Streams.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><a
href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GTypeInterface"
>GTypeInterface</a>&#160;<em class="structfield"><code>g_iface</code></em>;</span></p></td>
<td> The parent interface.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code>tell</code></em>&#160;()</span></p></td>
<td> Tells the current location within a stream.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code>can_seek</code></em>&#160;()</span></p></td>
<td> Checks if seeking is supported by the stream.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code>seek</code></em>&#160;()</span></p></td>
<td> Seeks to a location within a stream.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code>can_truncate</code></em>&#160;()</span></p></td>
<td> Chekcs if truncation is suppored by the stream.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="structfield"><code>truncate_fn</code></em>&#160;()</span></p></td>
<td> Truncates a stream.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2749896"></a><h3>
<a name="g-seekable-tell"></a>g_seekable_tell ()</h3>
<a class="indexterm" name="id2749908"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
>goffset</a>             g_seekable_tell                     (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable);</pre>
<p>
Tells the current position within the stream.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>seekable</code></em>&#160;:</span></p></td>
<td> a <a class="link" href="GSeekable.html" title="GSeekable"><span class="type">GSeekable</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> the offset from the beginning of the buffer.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2749977"></a><h3>
<a name="g-seekable-can-seek"></a>g_seekable_can_seek ()</h3>
<a class="indexterm" name="id2749990"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            g_seekable_can_seek                 (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable);</pre>
<p>
Tests if the stream supports the <a class="link" href="GSeekable.html#GSeekableIface"><span class="type">GSeekableIface</span></a>.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>seekable</code></em>&#160;:</span></p></td>
<td> a <a class="link" href="GSeekable.html" title="GSeekable"><span class="type">GSeekable</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"
><code class="literal">TRUE</code></a> if <em class="parameter"><code>seekable</code></em> can be seeked. <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"
><code class="literal">FALSE</code></a> otherwise.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2750089"></a><h3>
<a name="g-seekable-seek"></a>g_seekable_seek ()</h3>
<a class="indexterm" name="id2750101"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            g_seekable_seek                     (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
>goffset</a> offset,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-IO-Channels.html#GSeekType"
>GSeekType</a> type,
                                                         <a class="link" href="GCancellable.html" title="GCancellable">GCancellable</a> *cancellable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Error-Reporting.html#GError"
>GError</a> **error);</pre>
<p>
Seeks in the stream by the given <em class="parameter"><code>offset</code></em>, modified by <em class="parameter"><code>type</code></em>.
</p>
<p>
If <em class="parameter"><code>cancellable</code></em> is not <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"
><code class="literal">NULL</code></a>, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error <a class="link" href="gio-GIOError.html#G-IO-ERROR-CANCELLED:CAPS"><code class="literal">G_IO_ERROR_CANCELLED</code></a> will be returned.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>seekable</code></em>&#160;:</span></p></td>
<td> a <a class="link" href="GSeekable.html" title="GSeekable"><span class="type">GSeekable</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>offset</code></em>&#160;:</span></p></td>
<td> a <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
><span class="type">goffset</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>type</code></em>&#160;:</span></p></td>
<td> a <a
href="/usr/share/gtk-doc/html/glib/glib-IO-Channels.html#GSeekType"
><span class="type">GSeekType</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>cancellable</code></em>&#160;:</span></p></td>
<td> optional <a class="link" href="GCancellable.html" title="GCancellable"><span class="type">GCancellable</span></a> object, <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"
><code class="literal">NULL</code></a> to ignore. 
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>error</code></em>&#160;:</span></p></td>
<td> a <a
href="/usr/share/gtk-doc/html/glib/glib-Error-Reporting.html#GError"
><span class="type">GError</span></a> location to store the error occuring, or <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"
><code class="literal">NULL</code></a> to 
ignore.
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"
><code class="literal">TRUE</code></a> if successful. If an error
    has occurred, this function will return <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"
><code class="literal">FALSE</code></a> and set <em class="parameter"><code>error</code></em>
    appropriately if present.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2750369"></a><h3>
<a name="g-seekable-can-truncate"></a>g_seekable_can_truncate ()</h3>
<a class="indexterm" name="id2750380"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            g_seekable_can_truncate             (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable);</pre>
<p>
Tests if the stream can be truncated.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>seekable</code></em>&#160;:</span></p></td>
<td> a <a class="link" href="GSeekable.html" title="GSeekable"><span class="type">GSeekable</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"
><code class="literal">TRUE</code></a> if the stream can be truncated, <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"
><code class="literal">FALSE</code></a> otherwise.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2846615"></a><h3>
<a name="g-seekable-truncate"></a>g_seekable_truncate ()</h3>
<a class="indexterm" name="id2846628"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"
>gboolean</a>            g_seekable_truncate                 (<a class="link" href="GSeekable.html" title="GSeekable">GSeekable</a> *seekable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
>goffset</a> offset,
                                                         <a class="link" href="GCancellable.html" title="GCancellable">GCancellable</a> *cancellable,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Error-Reporting.html#GError"
>GError</a> **error);</pre>
<p>
Truncates a stream with a given <span class="type">offset</span>. 
</p>
<p>
If <em class="parameter"><code>cancellable</code></em> is not <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"
><code class="literal">NULL</code></a>, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error <a class="link" href="gio-GIOError.html#G-IO-ERROR-CANCELLED:CAPS"><code class="literal">G_IO_ERROR_CANCELLED</code></a> will be returned. If an
operation was partially finished when the operation was cancelled the
partial result will be returned, without an error.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>seekable</code></em>&#160;:</span></p></td>
<td> a <a class="link" href="GSeekable.html" title="GSeekable"><span class="type">GSeekable</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>offset</code></em>&#160;:</span></p></td>
<td> a <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#goffset"
><span class="type">goffset</span></a>.
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>cancellable</code></em>&#160;:</span></p></td>
<td> optional <a class="link" href="GCancellable.html" title="GCancellable"><span class="type">GCancellable</span></a> object, <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"
><code class="literal">NULL</code></a> to ignore. 
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>error</code></em>&#160;:</span></p></td>
<td> a <a
href="/usr/share/gtk-doc/html/glib/glib-Error-Reporting.html#GError"
><span class="type">GError</span></a> location to store the error occuring, or <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"
><code class="literal">NULL</code></a> to 
ignore.
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"
><code class="literal">TRUE</code></a> if successful. If an error
    has occurred, this function will return <a
href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"
><code class="literal">FALSE</code></a> and set <em class="parameter"><code>error</code></em>
    appropriately if present. 
</td>
</tr>
</tbody>
</table></div>
</div>
</div>
<div class="refsect1" lang="en">
<a name="id2846865"></a><h2>See Also</h2>
<a class="link" href="GInputStream.html" title="GInputStream"><span class="type">GInputStream</span></a>, <a class="link" href="GOutputStream.html" title="GOutputStream"><span class="type">GOutputStream</span></a>
</div>
<div class="refsect1" lang="en">
<a name="id2846887"></a><div class="refsect2" lang="en"><a name="id2846888"></a></div>
<hr>
<div class="refsect2" lang="en"><a name="id2846889"></a></div>
</div>
</div>
</body>
</html>
